Can you ride ______bike?—Yes. What about going to the park by bike this coming Saturday?

The wallet must ________ LiLei’s. Look! It has his ID card in it.

Who is ___________ man under the tree?

Which T-shirt do you want to buy?– The ________ one

The whole world is undergoing the biggest financial crisis nowadays, ____ calls for international cooperation among all nations to get over.